I have no idea why your lights are shutting off. It does sound like it is
overheating to me. However, I don't know if your bulbs are getting too hot, or
your ballast perhaps...

Regarding lighting for your clams... go with Option 1. I'm about to follow
suit. I have dual 175w 10,000K bulbs going over my 55g as soon as the quick
connect cords arrive. I'll supplement with one 110w VHO actinic at first. If
that isn't enough, I'll add one more.

Marc


Dave Johnson wrote:

I've *finally* changed out the lighting over one of my tanks and added
400 W MH. My problem is that the bulb will fire for about 2 hours
and then shut down. After 10-12 minutes it turns back on again, then
goes off about 5-8 minutes later, repeating this cycle.

I've done some research and everything that I can find about on/off/on/off
indicates that it happens right away, not after 2 hours of being on.

The ballast is Advance M59 dual volt HID, Ushio 10,000K mogul bulb
(hellolights said would work fine with ballast) Is this a heat problem
or could it be part of the burn-in cycle or ???

Next for you clam owners:
If you had a choice between these 2 lighting scenarios, where would
you place a maxima or crocea clam?
1) 400 W MH 10,000K & 2x40 NO actinic 12 inches above water, water
to DSB = 15 inches
2) 4x110 W VHO & 2x40 NO actinic 5 inches above water, water to
DSB = 10 inches

I'm thinking #1 will give me the best penetration to the depth, anyone
disagree?

Thanks,
Dave Johnson

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